PrismDesk

Launching 14 October 2026 · Windows 11 · Android

The second monitor you already own.

PrismDesk turns an Android tablet into a wireless display for your Windows PC — in HDR, with pen input, and with numbers you can check before you trust it.

5.0Mbps Video at 2944×1840
8.9kbps Idle, on a still screen
0.5–1.3s To wake a still screen
4tablets Connected at once, verified

Three claims, three measurements

Every line on this page is something we measured.

Second-monitor apps are easy to demo and hard to live with. So instead of adjectives, here is what came out of the test rig — and below, exactly how it was measured.

0 steps after a PC restart

Set up nothing

The installer adds the display driver, the firewall rule and the start-up entry itself. After a reboot the PC is already listening — open the app on the tablet and the screen is there. No “Windows Defender Firewall has blocked this app”, no port forwarding, no account.

12 of 12 sessions recovered

It doesn’t break

Wi-Fi cut for 2, 5 and 10 seconds, four times each: every session came back on its own, onto the same virtual display. A tablet that leaves for good is cleaned up in 20.5 s, so you are never left dragging windows around a monitor that isn’t there.

hdrSdrRatio 7.999703

It does HDR

Measured on a Pixel 9: BT.2020 with a PQ transfer curve, end to end, with no silent fall back to SDR. HDR content on the PC arrives as HDR content on the tablet.

How this was measured. Host: Intel Core i7-11700, NVIDIA RTX 3060 + Intel UHD 750, Windows 11 (10.0 build 26200), gigabit Ethernet. Tablet: Lenovo Tab M11 (Android 16), 1840×2944, Wi-Fi 6 at −46 dBm, same layer-2 network. Figures come from outside the product — packet counts on the wire, GPU engine utilisation, and SurfaceFlinger frame timings on the tablet — not from the app’s own reporting. Bandwidth was measured on 1 September 2026, before transport encryption was added; a later run put the increase from encryption at roughly 2%. In the same test, on the same content, spacedesk used 24.7 Mbps. HDR was verified on a Pixel 9. Your numbers will differ with your resolution, your content and your network.

Three steps, once

How it works

Install it on the PC

One installer. It sets up a virtual display driver, so Windows sees a genuine extra monitor with its own resolution — not a mirrored window you have to arrange around.

Open the app on the tablet

It finds the PC on your network by itself. If you would rather be explicit, scan the QR code the PC shows, or type the address once.

Leave it alone

Drag windows onto it, draw on it, walk out of Wi-Fi range and come back. Restart the PC and it is waiting again without being asked.

Also true

What else it does

Pen
Pressure, tilt and rotation arrive on the PC as real Windows pen input, so pressure-sensitive apps see a pen and not a mouse.
Webcam
The tablet’s camera shows up on the PC as “PrismDesk Camera”, so you can pick it in Discord, Teams or OBS.
Four at once
Four tablets can connect to one PC, sharing a single capture and a single encoder. Four is the number we verified, so four is the number we publish.
Encrypted
TLS 1.3 on the control and input channels; AES-256-GCM on video, audio and camera. The tablet pins the PC’s certificate fingerprint.
Nothing leaves your network
No account, no server, no telemetry, no update check. The apps never contact us — pixels go straight from your PC to your tablet.
Quiet when idle
A still screen costs 8.9 kbps. Leaving a tablet propped up beside the monitor all day is not a bandwidth decision.

Price

US$22 One-time purchase. No subscription, no account.

The free edition covers the basics — one device, SDR, pen and touch input, and audio. Pro adds HDR, up to 16 devices at once, your device camera as a Windows webcam, high frame-rate profiles and gamepad support. Pro is sold by Polar Software, Inc. as merchant of record, and one key covers three of your own Windows PCs. If it does not work on a PC that meets the requirements and we cannot fix it with you, you get your money back within 14 days — see refunds.

Read this before you sign up

What it does not do — yet

A second monitor that disappoints you on day two is worse than one you never installed. These are the things we would want to know first.

  • It is not on Google Play yet. The Android app ships when the closed test finishes. That is what the email list is for.
  • Windows 11 only — 64-bit, build 22000 or later. Windows 10 is not supported, and we have not tested it, so we do not claim it.
  • Same network only. Your PC and tablet share a LAN. PrismDesk is not a way to reach your desktop from a café.
  • We do not advertise a frame rate. The rate follows what Windows composes: on a 75 Hz primary display the achievable rates are 75, 37.5 and 25 — 60 is simply not on that list. Anyone promising you a number is promising you their monitor, not yours.
  • Long-run stability is not measured. We have not yet published a multi-hour soak test, so we will not tell you it is rock solid overnight.
  • Five Android devices tested — Pixel 3, Pixel 6, Pixel 9, Lenovo Tab M11, Lenovo Idea Tab Pro. Budget hardware is untested. Try the free edition on your own tablet before you pay for anything.

Requirements. Windows 11 64-bit (build 22000 or later) with administrator rights, and a GPU that can encode H.264 in hardware — NVIDIA NVENC, or an Intel or AMD encoder through Media Foundation. Android 8.0 (API 26) or later with a hardware H.264 decoder. Both devices on the same LAN, wired or Wi-Fi.

One email, at launch

Tell me when it’s ready.

No drip sequence, no “10 productivity tips”. One message when PrismDesk is downloadable, and that is the whole plan.